1. Field of the Invention
The present invention relates to a boom assembly in a working vehicle, such as a front loader.
2. Description of Related Art
In a boom assembly of a front loader, for example, a front boom portion and a rear boom portion are curved at a center portion in a boom's length direction and are connected in a bowed shape protruding on an upper side. A left-right pair of side plates is fixedly positioned on both a left and right side of a rear portion side of the front boom portion and a front portion side of the rear boom portion. A central connection plate is attached between the pair of side plates, and a rear portion side of a cover plate on the front boom portion and a front portion side of a cover plate on the rear boom portion are connected thereby. A pivoting support for a working tool cylinder used to move a working tool connected to a foremost portion of a front boom assembly body is provided on a front side of a top portion on each of the left and right side plates.
In this type of boom assembly, in order to increase the strength in the area around the pivoting support for a working tool cylinder where stress is concentrated during excavation work and the like, it is possible to add a reinforcement plate to the area around the pivoting support. However, this negatively affects the appearance of the working vehicle. In a conventional boom assembly, the left and right side plates enable inclusion of the pivoting support for the working tool cylinder, and the thickness of the side plates is increased in an attempt to ensure strength and improve an external appearance (see, for example, Related Art 1).
[Related Art 1] Japanese Patent Laid-open Publication No. 2007-262689